The function this.listCatModel.push is not a valid operation

I have a dropdown that I want to populate using the following code:

 this.categoryService.GetListItem(this.GetAllcatListUrl).subscribe(data=>{
  this.listCatModel=data,
  this.listCatModel.push({
    id:0,
    name:'Main Category',
    parentId:0
  })
});

However, when I try to use the push method on this.listCatModel, I encounter the following error:

ERROR TypeError: _this.listCatModel.push is not a function

What could be causing this issue? How can I go about resolving it?

Answer №1

Before proceeding, make sure to start by initializing the array this.listCatModel = [].

Keep in mind that the function

this.categoryService.GetListItem()
is asynchronous, meaning it will continue running until you have successfully pushed the values into it.

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